package org.jboss.windup.util.xml;

import java.util.regex.Matcher;
import java.util.regex.Pattern;

import org.apache.commons.lang3.StringUtils;

public class NamespaceUtils {

    public static String extractVersion(String schemaLocation) {
        if (StringUtils.isBlank(schemaLocation)) {
            return null;
        }

        Pattern pattern = Pattern.compile("[0-9][0-9a-zA-Z_]+.xsd$");
        Matcher matcher = pattern.matcher(schemaLocation);
        if (matcher.find()) {
            String match = matcher.group();

            //for system ID, make sure to remove the ".dtd" that could come in.
            String version = StringUtils.removeEnd(match, ".xsd");
            version = StringUtils.replace(version, "_", ".");
            version = StringUtils.trimToNull(version);
            return version;
        }

        return null;
    }
}
